1. Field of the Invention
The present invention relates to an electrodeless lighting system and a control method thereof capable of avoiding communication interference with a wireless LAN by changing a filament current, and lengthening a life span of a magnetron.
2. Description of the Related Art
Recently, an electrodeless lighting system using microwave has been developed, and because the electrodeless lighting system has a long life span and good luminous efficiency and characteristics, it is increasingly used.
As shown in FIG. 3, a general electrodeless lighting system includes a magnetron 10 generating microwave (or ultrahigh frequency), a resonator 30 including an electrodeless light bulb 20 therein, resonating microwave supplied from the magnetron 10, and having a mesh form to discharge light, which has been converted from microwave energy in the light bulb, to its maximum level to outside, a wave guide 40 guiding the microwave generated by the magnetron 10 to the resonator 30, a high voltage generating unit 50 increasing external power into a high voltage and supplying the high voltage to the magnetron 10, a cooling unit 70 preventing the magnetron 10 and the high voltage generating unit 50 from being overheated due to heat generated by themselves, and a control unit controlling the high voltage generating unit 50 applying a high voltage to the magnetron 10 and the cooling unit 70.
The high voltage generating unit 50 increases AC power applied from an external source upon receiving a driving signal outputted from the control unit 60, and supplies the increased high voltage to the magnetron 10. The magnetron 10 is oscillated by the high voltage outputted from the high voltage generating unit 50 to concentrate the microwave having a very high frequency to the electrodeless light bulb within the resonator 30 through the wave guide 40, and accordingly, the electrodeless light bulb 20 absorbs the microwave energy to generate light.
Meanwhile, a wireless LAN is one of communication network schemes allowing connectors to wirelessly communicate with each other by using a radio frequency. According to an IEEE standard, the wireless LAN uses a high frequency of 2.4 GHz, 5 GHz, or the like. However, these microwave signals may affect other nearby electronic devices or may be affected by them to cause malfunction or the like, so the use of the high frequency signals is limited in airplanes, hospitals, laboratories, and the like.
In the related art, in order to secure an initial maneuverability of the electrodeless lighting system, a filament is sufficiently heated with a filament current and then voltage is applied to a magnetron high voltage driving unit in consideration of diurnal variations, e.g., temperature characteristics, of the magnetron.
However, the related art electrodeless lighting system and control method thereof do not have a function of regulating the amount of filament electron emission, causing interference with the wireless LAN.
In addition, in the related art electrodeless lighting system and control method thereof, there is not difference between an initial heating current and an operation current, so communication interference with the wireless LAN is generated due to noise generated from the electrodeless lighting system.